网格对高超声速钝头体表面热流数值模拟结果的影响

Effect of grid strategy on numerical simulation results of aerothermal heating loads over hypersonic blunt bodies

高超声速钝头体热流的精确预估,对高超声速飞行器热防护的设计具有重要意义,而网格划分尺度对预估飞行器表面热流精度具有重要的影响。应用理论分析及数值模拟方法,提出了一种基于壁面网格雷诺数及基于钝体特征长度的来流雷诺数网格划分方法,并给出了壁面网格雷诺数的取值范围。应用所提出的网格划分方法,对不同来流条件的高超声速半圆柱及球头表面热流进行了数值模拟,结果表明,应用所提出的网格划分方法,及给出的可供参考的壁面网格雷诺数的取值范围划分网格,在满足高超声速钝体表面热流精度要求的同时,有利于网格合理分布并提高数值计算效率。

Accurate prediction of aerothermal heating load over hypersonic blunt bodies is of great significance to the design of hypersonic vehicle thermal protection,while grid metric affects the prediction accuracy of aircraft surface heating load.By theoretical analysis and numerical simulation,a grid generation method is proposed according to the cell Reynolds number and freestream Reynolds number,respectively,based on the wall parameters and characteristic length of blunt bodies,and the reference value range of the cell Reynolds number based on wall parameters is also provided.The proposed grid generation method is then applied to the simulation of hypersonic aeroheating computations over semi-cylinders and semi-spheres under different incoming flow conditions.The results show that the proposed grid generation method and the suggested range of the cell Reynolds number based on wall parameters can satisfy the precision requirement of thermal environment simulation over hypersonic blunt bodies,facilitate the rational distribution of grids,and simultaneously improve the efficiency of numerical calculations.